Vapor-rectifier.



n. E. CARPENTER.

VAPOR RECTIFIER.

APPLICATION FILED JUNE 9.1914.

1,296,264. Patented Mar. 4,1919.

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`WITNESSES: v u* INVENTOR 62u mz gif/ ATTORNEY TE sTA'rEs ATENE`o'EEroE.

DAVID E. CARPENTER, OF'WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTING-HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

VAPOR-RECTIFIER.

Specication'of Letters Patent.

Patented Mar. 4, 1919.

Application 'led J une 9, 1914. Serial No. 843,943.

ing the permanency and steadiness ,of the arc when started.

In the accompanymg drawing, Figure 1 is a-view, partially in section andpartially in elevation, of a mercury vapor rectifier embodying myinvention; and Fig. 2 is aview, in section, of a portion of a mercuryvapor rectifier embodying a modified form of 'current supply.

As is well known in the art, the flow of an electric current throughv agas or an evacuated space is possible only when said gas or saidevacuated space contains ions or electrons. These ions or electrons aregenerally formed from the substance of one of the electrodes, generallythe cathode Accordingly, the flow of current through a mercury Lamp orrectifier is possible because of the presence of ions or electrons fromthe body of mercury constituting the cathode, I have found that, withthe extensive and complicated sy'stems of shielding now in use toprevent the throwing off of masses of molecular mercury from the body ofthe cathode and hence to prevent short circuiting between the anodes, 1tis difficult to obtain a suiiicient number of ions or electrons in theneighborhood of the lanodes, their free passage upward from the cathodebeing greatly obstructed by the tortuous path providedvforl the'arc. Ihave found that,by locating ion generating devices near the anodes andin proximity to points of inflection of the vapor arc, thus assuring aplentiful supply of ions at all portions on the vapor' path, a vaporrectifier may be started much more readily and its operation, whenstarted, may'l be rendered much more stable during wide fluctuations ofload and, of impressed voltage. Referring to the form of device shown inFig. 1, 3'is a container of substantially gasralso serves to restrict ttight material,l such, for example, as drawn' steel. The container 3 isprovided with a cover 4 and the two are joined by any suitable gas-tightseal. A pair ofv anodes 5 and (i project through thc coverinto theinterior of the container 3 and are supported therefrom by insulatinggas-tight seals 7 and 8. The anodes 5 and G are supplied withalternating current from a suitable source 9. A pool of mercury 10 inthe bottom of the container serves as the cathode, and current is takentherefrom through the wall of the container to a connection 11 leadingto a load 12. From the load 12, the rectified, current is returned by awire 13 to the-mid point of the source 9, all as is well known in theart. A rod of conducting material 14 projects through thev cover' andissupported vtherefrom by an insulating gas-tight seal 15. The lower endof the rod 14 is adjacent the upper surface of the cathode pool so that,by the application of a moderately high voltage for starting or by themovement ofthe rod 14 into and out of the cathode pool, a keepalive arcof the ordinary type may be maln- 4separate the central portion ofthecathode pool Vfrom the outer portions thereof and ie cathode activity tothe central portion of the pool. A disk 17 of refractory material, such,for example, as iron, having an' opening 1S in the central portionthereof, rests upon the upper edge of the ring 16 and serves to stillfurther confine the region of cathode activity. A frusto-conicalshielding member 19 is supported from the disk 17 by anyysuitable means,such, for example, as arms 20. The

rod 14 is insulated from the member 19 by a bushing 21. A tube 22'ofrefractory insulating material, such, for example, as quartz surroundsthe rod 14 and rests upon the member 19, shielding therod 14 from thevapor arc. Shielding members23 and 24, preferably constructed ofconducting'material, are supported from the sealing devices 7 and 8 inany suitable manner and render the direct arcing p ath'between theanodes relatively long and tortuous, since the arcing openings 25 and26Xface awayfromV each other. The breaking down` of the negativeelectrode reluctance of an anode is generally` caused by the impactthereupon of a body of molecular mercury thrownv off from the cathode bymeans of the cathode flame and, since the vapor are must rise throughthe opening 18, pass out under the-edge of the member 19 and passthrough the openings 25 and 26,.

it is extremely difficult for any cathode particles to impinge directlyupon the anodes.

l An electrode 27 projects through the r cover. and is insulated,throughout the greater part of its length, by an extension ofan-insulating seal 28 or by any equivalent means. A Geissler-tubedischarge is maintained between the lower end of the electrode 27 andthe wall 4of the container by means of any suitable source ofhigh-potential current, such, for example,'as an induction coil 29, theprimary winding of which is energized from ar'battery 30 which may 'alsosupply current to the keep-alive anode 33 'and the mercury in the cup 21by any suit- V14. A cup 31 Ais mounted on the wall of the container nearthe cathode and is insulated from the wall by insulating means32.Condensation from the wall will keep the cup 31 filled with mercury atall times. An

'auxiliary anode 33 is mounted adjacent the mercury in the cup as, forexample, by an extension of the insulating means 32. An

ionizing arc is maintained between the'anode able source 34 through afull wire circuit 35. l*Having thus described the structureuand relativearrangement of the various ele- 1 lments of my device, the operation isas fol lows: By the application of high-potential,

high-frequency, current or by any other suitable Astarting method, smalldirect current arcs are initiated between the lower 'end of the rod 14and the cathode pool 10 and between the anode 33 and the pool in member31. A Geissler-tube discharge isalso initiated between the anode 27 andthe wall of the container. By the operation of these discharges,the'interior of the container is filled with ions or electrons so that,upon.

supplying alternating current from the source 9, alternate waves will'owfrom the anodes 5 'and '6,y and rectification 'will be initiated in theusual manner.

Cups, similar to the member 31, might be ldisposed throughout thecontainer. to serve as sources of ionization -or meansmight beinstalled4 for maintaining Geissler discharges in' various parts of thecontainer for providing ions, as desired. v Obviously, the

v number and arrangementl of -the ionicsources must be vadapted tothespecific sys'y i. tem of )shielding employed between 'the main'anodesand the main cathode.

l Referring to the form of mydevice shown in Fig. 2, 38`is the wall of acontainer, pref erably ,of steel; 3-9 is one ofthe main anodes`supported-therein and `4 is the cathode pool,

all as in the device of Fig. 1. Members 41, 42, 43 and 44 are similar instructure andin function to the corres onding members in Fig. l1. A cupshape member 45 of nonma etic material such for example as nic el alloyis weided tothe edges o an opening in the wall of the container 38, asshown at 46. A winding 47 is slipped over the outer surface of the cupshaped member 45 and connected to any suitable alternating currentsource. A cup shaped member 48 of magnetic material, laminated ifdesired, is slipped over the Winding 47 and attached to the container byany suitable means shown at 49. A laminated mushroom magnetic coremember 50, carrying a plurality of windings 51,52 and 53, is mountedwithin the cup shaped member -45 and is entirely sealed within acontainer 54 of gas-ti ht material, such, for example, `as glass.neterminal of each of the windings 51, 52 and 53' is grounded on thewall of the container -by a wire 55. The' remaining terminal of thewinding 51 is connected, by a-wire 56, tol an anode 57 vsupportedadjacent the surface Having thus described the structure .of` Fig. 2,the operation is as follows: Upon suppl 'ng alternating current, to thewinding 4 an alternating magnetic flux is set up through the core member50,' the cup shaped member 48 and that portion of the container wallconstituting the edges of the opening in which is welded the member 45.Electromotive forces of any'desiredamount are generated within thewindings 51, 52, 53,

and the current flowing therefrom causes an arc between the anode 57 andthe and causes `the filaments 58 and v59 to become pool 40 incandescent.Ions or electrons are accordingly generated in` great numbers within thecontainer and, upon supplying analternating electromotive force throughthe main anodes, current flow and rectification will ensue. I Y

.The specific transforming device l45'54 employed for setting upcurrentflow ina plurality of separate circuits within a containervwithout the necessity of sealing al great number of wires through thewalls of the container, with liability to leakage,

forms no part of my invention but-is sepa- .lrately described andclaimedl in U. S. 1-"at-y ent No. 1,150,017, issued to Y) the Westingwhouse Electric & Manufacturing Company,

Aug. 17, 1915, on an application filed by David C. Davis. j Obviously,any other old and Well known means for generating ions by the currentflow in the small auxiliary circuits of Fig. 2 may be employed.

While I .have shown my' invention in two specific embodiments, I do notwish it to be restricted to the specific forms shown, but desire that itbe construed broadly to cover any and all means for generating ions orelectrpns at a plurality of points within the container -of vacuumelectric apparatus in order to promote theflow of current therethrough,and I desire that only such limitations shall be imposed upon myinvention as are set forthin the acco panying claims., I claim as myinvention:

A comprising an evacuated container and suitcomprising an evacuatedcontainer reventing 1. The combination with a vapor rectifier,

which points there are means preventing free ionic travel. Y

2. The combination with a Vaporrectiier,

and suitable/ working electrodes therein, of means independent of themain circuit for generating ions adjacent the main cathode, and means,also independent of the main circult, for generatin ions adjacent a mainanode.

3. The com ination with a vapor rectifier, comprising an evacuatedcontainer and suitable Working electrodes therein,'of means, includingan auxiliary circuit, for generating ions adjacent one portion of themain arc pathmeans, including lan auxlliary circuit, for generatingionsl adjacent another portion of the main arc path, and meansfor theflow of pulsating current rom one auxiliary circuit to the other.

vIn testimony w subscribed my name this 28th DAVID E. CARIJIENTER.

Witnesses:

G. R. GWIN,

B. B. HINES.

day of May hereof, Ihave hereunto

